northernbrewer.com. morebeer.com, and midwestsupplies.com are the three I tend to order from. If you just need hops freshops.com or hopsdirect.com are great as well.

For pH are you talking about your water pH? It is the mash pH that really matters. Some gypsum will lower the mash pH and adds sulfate which helps the hoppy bitterness come across as crisper. If you want to lower the sparge pH some lactic or phosphoric acid would be a good choice.

All of the ones listed are good. I especially like Freshops for leaf hops. They have been consistently high quality. Some of the other leaf hops I've purchased elsewhere are sometimes not as good as I would expect them to be. Locally I buy most of my hops from brewbrothers.biz .

Veyr helpful on all fronts. That is helpful about Gypsum. i was told once when I used it todo a clone that it was a for a clarifier but that particular recipe has had the best hop fllavor nad bitterness so far. I will read more about that. Thank you all.